RSC Advances
·
2018
·Vol. 8
·期 27
·15149-15157
·
IF 2.936
Wenhui Gao,Guangmei Zhai,Caifeng Zhang,Zhimeng Shao,Lulu Zheng,Yong Zhang,Yongzhen Yang,Xuemin Li,Xuguang Liu,Bingshe Xu
An initial improvement in performance of PbS quantum dot solar cells composed of one thick layer of PbS quantum dots (QDs) treated with tetrabutylammonium iodide (PbS–TBAI) and one thin layer of PbS QDs capped with 1,2-ethanedithiol (PbS–EDT) over short-term air exposure is widely observed. However, the underlying mechanisms still remain elusive. In the work, we sought to understand the mechanisms as well as their physicochemical origins using a combination of X-ray photoelectron spectroscopy (XPS) and various electronic measurements. It is found that the PbS–TBAI film plays a dominant role in the initial device performance improvement compared with the PbS–EDT film. The PbS–TBAI film is compensation doped upon short-term air exposure (one to three days) owing to the increase of Pb–O and/or Pb–OH species, enabling its energy band to align better with the electron transport layer for more efficient charge extraction. Moreover, it is demonstrated that the short-term air exposure is capable of reducing defects in the devices and improving the diode quality, resulting in an initial increase in device performance. This work contributes to the fundamental understanding of the surface chemistry changes of PbS quantum dots treated by different ligands over air-exposure and the role of surface chemistry of quantum dots in optimizing their photovoltaic performance.
研究领域:
材料科学
·
光伏技术
·
物理化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Jian Du,Jialong Duan,Xiya Yang,Qingwei Zhou,Yanyan Duan,Tingting Zhang,Qunwei Tang
Sluggish charge transfer in perovskite film induced by inherent defects such as uncoordinated Pb 2+ undoubtedly hinders the rapid response of self-powered photovoltaic-typed detector. Based on interaction between Lewis acids and bases, herein, we employ thiourea molecule as a multifunctional Lewis base to significantly improve the quality of all-inorganic CsPbIBr 2 perovskite film. After careful characterizations, the quality of perovskite film has been well regulated. Arising from the reduced defect and the reinforced the interfacial charge extraction owing to the strong interaction between uncoordinated Pb 2+ ions and the -C = S groups in thiourea and the formation of hydrogen bond at perovskite/TiO 2 interface, an enhanced responsivity of 0.335 A W −1 and specific detectivity of 3.92 × 10 12 Jones has been achieved for the self-powered, carbon-electrode based photodetector, which is comparable to the state-of-the-art device based on CsPbIBr 2 film. More importantly, the device free of encapsulation remains 82.8% of initial performance after storage over 56 days in ambient atmosphere, promoting the practical deployment of perovskite products.
研究领域:
材料科学
·
光电技术
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Wangying Xu,Zihao Zhang,Changjie Zhou,Deliang Zhu
Vacuum-free, solution-processable high-κ-oxide dielectrics are considered to be a key element for emerging low-cost flexible electronics. However, they usually suffer from low breakdown strength and frequency-dependent capacitance, which limit their broader applications. Here, we report a universal way to improve solution-based high-κ oxide dielectric properties (e.g., Al2O3, ZrO2, Ga2O3, Sc2O3, Ho2O3, and Sm2O3) by sulfate incorporation. In-depth characterization shows that sulfate incorporation could reduce hydrogen and oxygen vacancy-related defects in high-κ oxides, thereby improving the dielectric performance. The optimized S-doped high-κ oxides show smooth surface (rms < 0.20 nm), low leakage current (∼10–7 A/cm2@4 MV/cm), excellent dielectric breakdown strength (>10 MV/cm), and stable capacitance–frequency characteristics. Besides, oxide thin-film transistors based on these high-κ dielectrics exhibit excellent performance (e.g., mobility >20 cm2 V–1 s–1, on/off ratio of ∼107, threshold swing of ∼0.14 V dec–1, threshold voltage of ∼0 V, and hysteresis of ∼0.02 V). Thus, this work provides a general approach for the development of high-quality solution-based high-κ oxides for transistor circuitry.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2016
·Vol. 52
·期 2
·869-877
·
IF 2.302
Fan Shaohua,Wang Shikai,Xu Wenbin,Li Meng,Sun Hongtao,Hu Lili
Efficient upconversion (UC) microcrystals are important for the development of novel photonic markers, solid-state lasers, displays, etc. Herein, we report on greatly enhanced UC emission in β-NaYF 4 :20Yb,2Er microcrystals via a simple ion-exchange reaction. The ion exchange accompanying with an ionic redistribution process is demonstrated. By simply controlling the amount of NaF (0–8.0 mmol), reaction temperature (140–220 °C), and duration (0–144 h), enormous enhancement of the UC emission up to ~4200 times is obtained compared with the pre-synthesized β-NaYF 4 :20Yb,2Er microcrystals. The decrease of body defects and change of local structure around lanthanide may account for the UC emission enhancement. This method may apply to other UC materials to increase the UC emission efficiency.
研究领域:
材料科学
·
光子学
·
纳米技术
·
无机化学
·
发光材料
✓ 已验证
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 17
·4009
·
IF 4.2
Yongjun Wei,Feiping Lu,Xinqi Ai,Ju Lei,Yong Bai,Zhiang Wei,Ziyin Chen
Perovskite solar cells (PSCs) are considered the most promising photovoltaic devices to replace silicon-based solar cells because of their low preparation cost and high photoelectric conversion efficiency (PCE). Reducing defects in perovskite films is an effective means to improve the efficiency of PSCs. In this paper, a lead chelator was selected and mixed into hole transport layers (HTLs) to design and prepare mesoporous PSCs with the structure of ITO/PTAA(BCP)/Al2O3/PVK/PCBM/BCP/Ag, and its modification effect on the buried interface at the bottom of the perovskite layer in the mesoporous structure was explored. The experimental results show that in the presence of mesoporous alumina, the lead chelator can still play a role in modifying the bottom of the perovskite film. The use of lead chelator as passivation material added to the HTL can effectively reduce the residue of dimethyl sulfoxide (DMSO) and decrease the defects at the bottom of the perovskite film, which dramatically improves the device performance. The PCE of the device is increased from 18.03% to 20.78%, which is an increase of 15%. The work in this paper provides an effective method to enhance the performance of PSCs.
研究领域:
材料科学
·
能源技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Yiping Wang,Yang Jin,Yanjun Zhong,Pan Zhu,Jun Li
Iron based Prussian blue analogues (Fe-PBA) hold significant promise cathode materials for sodium ion batteries due to their low cost and desirable electrochemical properties. However, their practical application is often hindered by the presence of vacancy defects and issues of oxidation that arise during the material preparation process. To overcome these challenges, this study introduces an innovative T-shaped collision microreactor aimed at promoting a uniform concentration field, narrowing the gap between material mixing rate and reaction rate, and providing an oxygen-free environment for the synthesis of Fe-PBA. Employing this microreactor, Fe-PBAs were synthesized with a meticulous approach that led to a material possessing a well-defined morphology and a stoichiometry of Na1.54Fe[Fe(CN)6]0.93. The material exhibited a notable reduction in vacancy defects and minimized oxidation levels. Upon electrochemical evaluation, the Fe-PBA crafted within the microreactor demonstrated an impressive specific capacity of 94.1 mAh/g at a current density of 0.5 C and showcased a long-term cyclability with 72.6% capacity retention over 2000 cycles. Comparative analysis revealed that the structural and electrochemical properties of Fe-PBA prepared in the microreactor outperformed those of samples prepared using traditional reactors. This work provides a new approach for the continuous and stable fabrication of high-performance battery cathode materials.
研究领域:
材料科学
·
电化学
·
能源存储
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Energy Materials
·
2025
·
IF 5.5
Siguang Li,Minghua Li,Yiyang Wang,Xin Jiang,Zhe Liu,Yufei Gong,Meng Yuan,Tianwei Zou,Ruihan Wu,Siyu Zhuang,Senyao Wang,Shucheng Qin,Lei Meng,Yongfang Li
The inverted inorganic CsPbI3 perovskite solar cells (pero-SCs) show lower efficiency compared to the organic–inorganic hybrid pero-SCs, mainly due to its wide bandgap and poor fill factor (FF). Here, by doping a multifunctional additive, 4-(1,3,5-Triaza-7-phosphaadamantan-1-ium-1-yl)butane-1-sulfonate (PTABS), the compact perovskite film forms and grows into large grains during thermal annealing through the ripening process. Moreover, the evaporation of DMAI is accelerated owing to the hydrogen bond formed between DMAI and PTABS, which limits the invasion of moisture during annealing. After the evaporation of DMAI, the remaining PTABS coordinates with the Pb2+ ions and reduces the defects. Consequently, a high FF of 86.17% is reached, and the power conversion efficiency of the inverted CsPbI3 pero-SCs is improved to 22.09%. The stability is also improved, owing to the decreasing defects. This work emphasizes the significance of controlling the crystallization process in improving the efficiency of inorganic CsPbI3 pero-SCs.
研究领域:
材料科学
·
光伏技术
·
纳米技术
·
固体物理
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）